[tbb-bugs] #26557 [Applications/Tor Browser]: Regression in keyboard fingerprinting

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#26557: Regression in keyboard fingerprinting
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     Reporter:  pege                      |      Owner:  tbb-team
         Type:  defect                    |     Status:  new
     Priority:  Medium                    |  Milestone:
    Component:  Applications/Tor Browser  |    Version:
     Severity:  Normal                    |   Keywords:  ff60-esr
Actual Points:                            |  Parent ID:
       Points:                            |   Reviewer:
      Sponsor:                            |
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 I just compared fingerprinting protection between 8.0a8 and 8.0a9. There
 appears to be a regression when it comes to key combination with AtlGraph.

 My system:

 OS: Whonix 14 (Debian stretch) on Qubes OS 4.0
 Keyboard layout: Neo (https://neo-layout.org/index_en.html)


 For testing I used
 https://arthuredelstein.github.io/tordemos/keyboard.html.

 There are several keys that have regressed:

 == Numbers

 When typing the number 0 using the key pad on layer 4 ('<' + space) I
 observe this differences:

 8.0a8: code: Digit0, modifierState: empty
 8.0a9: code: Space, modifierState: AltGraph

 Similarly, other numbers, when typing using the number pad on layer 4,
 show the actual key that was pressed (KeyM, KeyJ, KeyU, …) instead of
 DigitX.

 == Navigation Keys

 Arrow up:

 8.0a8: code: ArrowUp, modifierState: empty
 8.0a9: code: ArrowUp, modifierState: AltGraph

 The modifier leaks with many of the keys on layer 4. Including, all arrow
 keys, escape, home, end, delete, back and comma. Interestingly, period and
 colon don't leak the modifier.

 I also noticed that colon is recognized as semicolon (on all layers) but
 that's also the case in older Tor Browser version.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/26557>
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